Kerry J. Byrnes Collection., A paper prepared for presentation at the 1978 Annual Meetings of the Rural Sociological Society, San Francisco, California. 8 pages., The paper reviews 10 studies which employed Guttman scaling to measure differentiation at the community level in developing countries. Three alternative approaches (content validation, criterion validation, and construct validation) are applied to assess the validity of the Guttman-type scale of community differentiation.